Making Football flying through uprights looks more natural

[Karl-jason Mawdsley]

The problem probably isn\’t the ball physics, it\’s probably your keyframes. You should try using the graph editor. Nick Campbell has a great tutorial on keyframes and the graph editor here: https://greyscalegorilla.com/blog/2009/03/guide-to-keyframes-in-after-effects/

Hope this helps.

KJ Mawdsley
Editor/Mograph Designer

[Chris Wright]

another consideration is to visit the AE expression forum here. If I remember correctly, Dan has a 1/2gt^2 formula hidden in the search. Also, most footballs have a slight wobble on the z axis, no matter how perfect the spin.

ahhh, here it is…
https://forums.creativecow.net/archivepost/2/502053

https://technicolorsoftware.hostzi.com/

[Ben Mettler]

So I’ve been messing around with the graph editor and trying to slow the Football down at the apex using only two key frames. What I’m having trouble with is using the handles to slow the speed down to where the apex is. I can only get it down to about 450 px/sec without moving the key-frames themselves. Also, why can’t I move the key-frames down to maybe 300 px/sec and then using the handles to get the apex to around 50 px/sec? Whenever I move the key-frames down the curve goes back up? I’ll attach a pic. The Time Indicator is where the apex is.

[Chris Buttacoli]

Are you animating the x and y paramaters separately?

[Ben Mettler]

I’m not sure. I guess not intentionally? I mean in the Value Graph there are values for X and Y. I animated it by just moving the Football to the positions I wanted it in.

[Chris Buttacoli]

I think you will have better results if you animate x pos and y pos separately, using expressions.

Try this, I hope you can follow me… it will animate a square going left to right.

Create a new composition, 2 seconds in duration. (I used default NTSC DV widescreen)
Create a new solid. Make the size 20 by 20.
Create two null objects. Call the first one “Xpos” and the second one “Ypos”.
Alt-click the position stop watch of the white solid.
Type or paste this expression:

x = thisComp.layer(“Xpos”).transform.position[0];
y = thisComp.layer(“Ypos”).transform.position[1];
[x,y]

Animate the Xpos null. At frame 0 set the position value to -75,0. Click and set the keyframe. At frame 59 set the value to 800,0. (Notice I am just animating the x coordinate.)
Animate the Ypos null. At frame 0 set the position value to 0,437. Click and set the keyframe. At frame 59 set the value the same by clicking the keyframe again. Now go to the middle of the comp (1 sec) and set a key with a value of 0,86. (Notice this time I am just animating the y coordinate.) Give this middle keyframe an easy ease.

What I have done is used the first null to animate the side to side ‘x’ motion, which is constant. The second null was used to animate the up and down ‘y’ motion, which goes up, slowly stops, and comes back down due to the easy-ease. I’m sure there are more efficient ways to do this, but I think this is pretty easy to try out, and hopefully conform to your football project. Or at least give you a BASIC idea what I was thinking.